The comments come from his new book Decision Points — the presidential memoir that hit the bookstores today.

Although decisions related to the 9-11 terrorist attacks, invading Iraq, the surge, Hurricane Katrina and other topics naturally dominate the list, Bush included the decision hailed by pro-life groups and eventually overturned by President Barack Obama.

He talked about how he struggled with the decision — in part because he, like so many Americans, was not well-versed on the subject of stem cell research back in the early stages of the national debate in 2001.

“First of all, what is a stem cell?” he said he asked domestic policy adviser Margaret Spellings during his first briefing on the topic.

He eventually educated himself on the subject and received advice from University of Chicago professor Leon Kass, who would go on to become the chairman of the presidential bioethics council he created.

Bush admitted he felt pulled to support embryonic stem cell research out of the shared concerns pro-life advocates have with backers of the destructive research for those suffering from incurable diseases or devastating medical issues.

“I felt pulled in both directions,” Bush wrote. “I had no interest in joining the Flat Earth Society. I empathized with the hopes for new medical cures. I had lost a sister to childhood leukemia. I worried that sanctioning the destruction of human embryos for research would be a step down the slippery slope from science fiction to medical reality.”

During the decision-making process, Bush heard from Republican senators Orrin Hatch and Strom Thurmond, former National Institutes of Health (NIH) director Harold Varmus, and received a written plea from former first lady Nancy Reagan. But he also heard from the National Right to Life Committee, which highlighted the program run by Nightlight Christian Adopti for the adoption of supposedly “leftover” embryos.

He even recalled how adviser Jay Lefkowitz read aloud to him in the Oval Office from Aldous Huxley’s 1932 tome Brave New World.

Bush even asked a Parkinson-disease stricken Pope John Paul II — “He was firm in his view that human life must be protected in all its forms,” Bush recalled.

But he writes that he ultimately came to the conclusion of the pro-life movement: “the science was unproven, the morality was in doubt, and ethical alternatives existed.”

Kass, in the end, had the most sway over the president, telling him he could fund research on embryonic stem cells that were already around and there human life would not be destroyed.

“If you fund research on lines that have already been developed,” Kass said, “you are not complicit in their destruction.”

“I made this decision with great care, and I pray it is the right one,” Bush said of his decision to stop taxpayer dollars from financing new embryonic stem cell research. “I did feel a responsibility to voice my pro-life convictions and lead the country toward what Pope John Paul II called a culture of life.”

Bush was immediately attacked from the left for the decision.

“Democrats …concluded that stem cell research was a political winner. It allowed them to open a new front in the abortion debate while also claiming the mantle of compassion,” he writes.

Bush points out his was the first presidential administration to allow federal funding for stem cell research and he acknowledges his decision to allow funding of embryonic stem cells that did not require the additional destruction of human life caused some controversy.

He says he is proud of his decision to direct considerable funds towards adult stem cell research — which pro-life groups repeatedly point out is the only form of stem cell research to help patients with any diseases or medical conditions.

He said the funding “yielded new treatments for patients suffering from dozens of diseases— free of moral drawbacks” including use of umbilical cord stem cells to treat patients.

But he notes how the first veto he ever signed as president was against a Democratic-approved bill that would have opened taxpayer funding, for the first time, to destroying human embryos specifically for their stem cells for research.

Looking back, he said he would not have changed his position.

“I would not change my position,” he writes. “If I abandoned my principles on an issue like stem cell research, how could I maintain my credibility on anything else?”

In fact, he hgilights research on direct reprogramming and IPSCs as validating his decision.

“I was thrilled by the news,” Bush writes about the 2007 paper form Japan showing scientists making embryonic-like cells without killing human beings. By adding just four genes to the adult [skin] cell, scientists were able to replicate the medical promise of embryonic stem cells without moral controversy.”